Compression ignition engines commonly have a timing mechanism to time the injection of fuel into the combustion chambers in response to engine speed for improving the efficiency and economy of the engine. Also, proper timing is critical for reducing the emission of noxious matter and excessive cylinder pressures. Such timing mechanism usually includes a system for interconnecting a pair of shafts so that their angular relationship can be varied in response to the movement of a pair of centrifugally actuated flyweights. While such timing mechanism effectively varies engine timing over the selected speed range in response to engine speed, the initial or static position of the shafts is set with the engine stopped because of the relatively high torque generated in the pump shaft due to the inherently high fluid pressure created by the fuel injection pumps. Heretofore the static positioning of the shafts has been dependent upon the proper alignment of timing marks on the gears of the timing gear train. However, setting the timing by the use of such timing marks does not compensate for the build up of manufacturing tolerances or the normal backlash in the gear train. Furthermore, such timing mechanism has the undesirable characteristic that even though the fuel pump shaft is advanced with increased engine speed, frequently the timing is retarded or backed down toward the initial setting by the pump force and resulting torque action on the timing mechanism.